Question

Identify the correct sequence of blood coagulation.
a. Activation of prothrombin.
b. Formation of prothrombin activator.
c. Formation of blood clot.
d. Conversion of fibrinogen to fibrin.

A. b-d-a-c
B. b-a-d-c
C. a-d-c-b
D. a-b-c-d

Answer 1

Blood coagulation is also known as Blood clotting. It is the process by which the blood changes from liquid state to gel state. When a clot occurs, both platelets and proteins work together to stop the bleeding by forming a clot over injury.

Complete answer:
Blood Coagulation occurs in the following sequence:
A prothrombin activator complex is formed due to the rupture of blood vessels and damage in the blood. The activator converts prothrombin into thrombin. Thrombin acts as an enzyme and converts fibrinogen into fibrin threads. Fibrin threads accumulate and dump to form blood clots at the wound site.
Simplified representation of steps of blood clotting:
Prothromboplastin in the presence of calcium ion gets converted to thromboplastin. Prothrombin acts on thromboplastin in the presence of calcium and further forms thrombin. The soluble fibrinogen gets converted in fibrin which is insoluble in the presence of thrombin. This fibrin starts forming mesh like structure at the place of injury leading to blood clot.
EXAMPLE:
The major example for clotting of blood is: -
Formation of yogurt-milk proteins coagulate to thick the mixture that forms yogurt.

Hence, the correct answer is option (B).

Additional information:
-Blood coagulation is a cascade.
-There are many clotting factors which activate the next protein.
-Blood clot results in hemostasis, which occurs due to the cessation of blood loss from a damaged vessel which continuously forms a repair.

Note: Blood clots are formed due to the certain parts of the blood being thickened, which forms a semisolid mass. It occurs with the help of a cascade of proteins that takes part in the process along with several factors and enzymes responsible in the process.